Federal authorities say that a railway signaling system in South Carolina was down for maintenance when an Amtrak train crashed into a CSX freight locomotive on Sunday, causing the deaths of an Amtrak engineer and conductor. (Feb. 5) AP

The crashes appear to stem from different causes, and federal investigators are sifting through each to find out what happened.

Here's what is going on with Amtrak, its safety record and criticism in Congress about its subsidies:

What accidents focused attention to Amtrak?

- Feb. 4, 2018: An Amtrak train collided with a CSX freight train parked on a siding in Cayce, S.C., killing the train's engineer and conductor. Investigators said a switch was locked to shunt the Amtrak train onto the siding and toward the parked train. Investigators said work crews were updating automatic-braking technology on the tracks when the accident occurred.

- Jan. 31, 2018: An Amtrak train collided with a garbage truck at a crossing in Crozet, Va., killing the truck driver. The crossing had crossbars and warning lights.

- April 3, 2016: An Amtrak train going 99 mph near Philadelphia slammed into a backhoe on the track, killing two workmen and injuring 39 people on the train. Federal investigations found a series of safety lapses - including a lapse in communications that failed to notify trains that the track was closed - led to the crash.

- May 12, 2015: A train traveling 106 mph into a 50-mph curve in Philadelphia derailed, killing eight passengers and injuring hundreds. Investigators ruled the engineer lost awareness of where he was on the route.

Amtrak CEO Richard Anderson, who joined the railroad last year after years as an airline executive, vowed after the last two accidents to improve safety at the railroad.

"Amtrak is fully committed and values safety as its highest priority," Anderson said in a statement Sunday. "In a word we've got to bring the same focus and safety culture you have at an airline to the railroad industry of America."

How often does Amtrak have accidents?

The number of fatalities involving Amtrak trains has been rising for the past decade, from 119 in 2008 to 167 last year through November 2017, according to the Federal Railroad Administration.

Only 12 of those deaths involved passengers aboard trains. (The three passengers killed in December aren't included yet in the statistics.) The vast majority of rail deaths involve pedestrians trespassing along the tracks or collisions with vehicles at road crossings, rather than train passengers.

The rate of Amtrak accidents per million train miles traveled grew from 41.1 in 2008 to nearly 58.8 by November 2017, according to FRA.

The number of trespasser deaths climbed from 70 to 103 during that same time period, according to FRA. The number of deaths in highway-rail accidents like the one last month in Crozet, Va., grew from 47 to 60 during that period, according to FRA.

But the rate of train accidents per million miles traveled that weren't at road crossings dropped steadily during the last decade, from nearly 2.4 in 2008 to 1.4 through November 2017, according to FRA.

Earl Weener, a member of the National Transportation Safety Board, was asked the day of the Crozet crash whether there were too many road collisions with railroads.

"I would agree that there are too many," Weener said. "We've investigated several just in the last couple of years. There are a lot of fatalities at (road) crossings, and that has become an area of focus."

Are Amtrak engineers experienced?

The engineers in recent Amtrak crashes each had several years of experience under their belts.

The 55-year-old engineer in the derailment in DuPont, Wash., was hired by Amtrak as a conductor in 2004 and promoted to locomotive engineer in 2013.

The 47-year-old engineer in the backhoe collision began training as an Amtrak engineer in May 2015 and was promoted to locomotive engineer in June 2015. He earlier worked for more than a decade as an engineer and in other jobs with New Jersey Transit.

The 31-year-old engineer in the Philadelphia derailment was hired by Amtrak as an assistant conductor in 2006 and after attending locomotive school he became a certified engineer in 2010, starting in the New York area in 2013.

What steps are being taken to prevent accidents?

Amtrak adopted technology for automatic braking in 2015 on its Northeast Corridor, which safety experts say could have prevented several of the recent accidents.

Najmedin Meshkati, an engineering professor at the University of Southern California, said installing braking technology called Positive Train Control is complicated because it must communicate across a variety of railroads and tracks and locomotives.

Amtrak trains often run on tracks owned by others, such as the CSX freight railroad in the South Carolina collision or Central Puget Sound Regional Transit Authority in the Washington derailment.

"They basically try to install that on a patchwork of rails and dispatch centers," Meshkati said. "You need to do a lot of coordination and activities."

Automatic braking also won't prevent every accident, such as at road crossings like the collision in Virginia with a garbage truck or the backhoe collision when the braking equipment wasn't operating.

"At the end of the day, it comes to the safety culture of each one of these railways," Meshkati said.

Amtrak passengers don't need to stop riding the railroad because of the rare but consequential accidents, he said. But passengers and Congress and the industry should work harder to reduce safety risks and prevent accidents, he said.

"I would say at the end of the day we may be playing Russian roulette," he said. "We need to eliminate the chance of failure."

How popular is Amtrak?

Amtrak carried nearly 31.3 million passengers in 2016, for an average of nearly 85,700 passengers daily on more than 300 trains. Amtrak divided its ridership and ticket revenue into three categories:

- State-supported routes, the most popular of which are the Capitol Corridor or the Keystone: 14.7 million passengers for $490 million in ticket revenue.

- Long-distance routes, the most popular of which are the Empire Builder or the California Zephyr: 4.7 million passengers for $492 million in ticket revenue.

If compared to airlines, Amtrak said it would be the fifth-largest carrier in the country for domestic passengers behind Southwest, American, Delta, United and JetBlue.

Amtrak is even more popular along the Northeast Corridor from Washington, D.C., to Boston. The railroad carries three times as many passengers as airlines between Washington and New York, and more than the airlines between New York and Boston.

What are the financial arguments against Amtrak?

Amtrak is routinely criticized for subsidies, but it retains strong support in Congress with 500 destinations in 46 states.

President Trump proposed in his budget for the year that began Oct. 1 to reduce Amtrak subsidies for long-distance service $630 million - nearly half the $1.4 billion provided the previous year - by arguing that trains were often late and operate at a loss.

But as Congress continues to debate spending, a key Senate panel agreed to provide $1.6 billion for Amtrak and continue all current routes. The key House panel agreed to provide $1.4 billion.

Comment: Even though in this instance, according to the article, safety incidents are actually steadily decreasing, America's infrastructure is failing, so it appears that the publicity these accidents receive is a factor in the public's concern. Travelling by rail can be a relatively pain-free experience when compared to the invasive and unjust security checks one has to suffer when flying, and if we look to how other countries are managing their rail network, it seems the west has a lot to learn:

The most successful tyranny is not the one that uses force to assure uniformity but the one that removes the awareness of other possibilities, that makes it seem inconceivable that other ways are viable, that removes the sense that there is an outside.